Add unconfirmed plug state 3 (#1304)

* added plugstate as 3 for waiting for charge

* Apply suggestions from code review

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Co-authored-by: epenet <6771947+epenet@users.noreply.github.com>

src/renault_api/kamereon/enums.py

@@ -22,6 +22,8 @@ class PlugState(Enum):
 
     UNPLUGGED = 0
     PLUGGED = 1
+    # 3 is unconfirmed, as it is currently unsupported on the App (see #1262)
+    PLUGGED_WAITING_FOR_CHARGE = 3
     PLUG_ERROR = -1
     PLUG_UNKNOWN = -2147483648